SLOA326 October   2022 TAS2781

 

  1.   Abstract
  2.   Trademarks
  3. 1Introduction
  4. 2Hybrid-Pro Boost Controller
  5. 3Hardware, Software, and Test Results
    1. 3.1 Hardware Connections
      1. 3.1.1 Schematic Connections
      2. 3.1.2 Equations
    2. 3.2 Software Settings
      1. 3.2.1 Steps To Enable Class-H Using PPC3
      2. 3.2.2 Class-H Configuration Settings
    3. 3.3 Hybrid-Pro Feature Performance Results
      1. 3.3.1 Class-H Operation
        1. 3.3.1.1 PWM Steps
        2. 3.3.1.2 Lookahead Time
        3. 3.3.1.3 Margin
        4. 3.3.1.4 Inflation Factor
      2. 3.3.2 Battery Life
      3. 3.3.3 Thermal Performance
  6. 4References

3.3.1 Class-H Operation

The output of the boost converter (PVDDH rail of TAS278x) with and without class-H operation is shown in Figure 3-6 through Figure 3-6. The output of the boost converter is set to a constant voltage when the class-H operation is disabled by disconnecting jumper J14 on the TAS278x EVM. The output voltage of the boost converter follows the envelope of the audio waveform when the class-H operation is enabled.

For all the following test waveforms, the hardware setup is TAS2781 EVM using PPC3, AVDD = IOVDD = 1.8 V, load = 8 Ω + 15 µH, PVDDL = 5 V, boost input = 4.2 V. The following waveforms show the differential output of the TAS278x (OUTP – OUTM) and the PVDDH.